2(3)-四-(2-异丙基-5-甲基苯氧基)钛氧酞菁的合成及其近红外发光特性

Synthesis and Near-infrared Luminescence of Tetra-(2-isopropyl-5-methylphenoxylphthalocyaninato)titanium(Ⅵ)Oxide

通过分步合成的方法,在钛氧酞菁的外围引入了四个苯氧基团,合成了一种2(3)-四-(2-异丙基-5-甲基苯氧基)钛氧酞菁。通过质谱、核磁、元素分析、紫外可见吸收光谱、近红外光荧光谱和循环伏安法对其结构和性质进行了表征,并利用旋涂加真空热蒸发的方法制得了该材料的电致发光器件(ITO/PVK∶TiOPc/BCP/LiF/Al)。结果表明,四取代的钛氧酞菁固态的近红外光荧光峰值在1 080 nm左右;其近红外电致发光的峰值波长落在1 050 nm左右。在PVK掺杂的器件中,钛氧酞菁的质量分数为30%时有较强的发光强度。

Recently the development of emissive materials for organic light-emitting diodes （OLEDs） in the NIR region is becoming a major research subject since such materials can provide a new type of NIR lightemitting device applicable to future optical communication and information processing. However, most of materials for use in NIR OLEDs were organic complexes with trivalent rare earth ions such as Er^3＋ , Nd^3＋ ,Tm^3＋ and Yb^3＋. However, since the f-f transition is, in principle, a parity-forbidden process, there is a substantial problem as regards the EL quantum efficiency. In this paper an organic material containing no rare earth ions： tetra-（2-isopropyl-5-methylphenoxylphthalocyaninato） titanium （Ⅳ） oxide was prepared and characterized by lit NMR, MS, elemental analysis, UV-vis absorption spectra, NIR PL spectra and cyclic voltammetry. The OLEDs based on this TiOPc was prepared by spin-coating and thermal evaporation. The structure of device is （ITO/PVK： TiOPc/BCP/LiF/Al）. From ^1H NMR, MS, elemental analysis we could found the excellent purity of this TiOPc. Cyclic voltammetry give us HOMO and LOMO level as - 5.26, - 3.69 eV, respectively. The NIR PL spectra show there is a broad band peaked at 1 080 nm. The electroluminescent（EL） devices with the TiOPc complex as the emitting layer were fabricated and they exhibit EL emission peaked at 1 050 nm. In the TiOPc-doped devices the optimum concentration was 30% （mass fraction ）, whir the intensity of NIR EL extremely high. This work is an original work of OLEDs in NIR region, so the efficiency and life should be improve in the future.